hello, we asked to simulate this signal conditioning examples in Proteus the example is case 3 and case 4 the problem when i put the input which is negative the out put is always 5 volt please i need help to simulate the case 3 and 4 examples in pdf file what is the wrong in my simulation

Looking at case 4: The voltage at the + (non-inverting) input is zero tied to ground.

What is the allowed input common-mode range for this amplifier when it is operated from 0V and 10V?

Considering that the output swing of the LM324 is from near oV to 10V-1.5V = 8.5V, and that the current injected by R1, R2 from the 5V bias source is tiny, what is the allowed input range from RG2 that would keep the opamp in its linear region (simple algebra, you dont need a simulator)?